??????, Master of Sea, Wa ga na wa Umishi, My Name is Umishi

Salvors are men responsible for towing wrecked ships and handling the cargos. They are different from rescue teams as they usually ask for money before offering help. Nanba Rintarou's father was the owner of such a company, but Rintarou really hated the way they operated and decided to join the Coast Guard
However, Rintarou's father died right after Rintarou completed his training. In his will he asked Rintarou to take over his company. What's worse is he left his son a debt of 1.5 billion yen...